The Rook 179 



increasing, occasionally wandering to the Outer Hebrides and now breeding as 

 far north as the Orkneys and Shetlands. 



The male Rook is black, glossed with purple, most brightly on the upper 

 parts. From the base of the bill is a l^are grey warty patch, extending over the 

 chin and upper part of the throat. Bill and feet black; iris brown. Tlie female 

 is slightly smaller and less glossy than the male. Tlie young bird is still less 

 glossy and has the base of the bill covered, as in the Carrion-Crow, with 

 bristly feathers; it may be distinguished by its more .slender bill and tlie deep flesh- 

 colour of the inside of the mouth, this, however, changes to .slate-colour with age. 



In England the Rook is a useful bird so long as it can obtain a sufficient 

 quantity of insects and their larvje to support it and its offspring ; but when, 

 owing to protracted drought it cannot obtain these, it becomes somewhat 

 mischievous after the fashion of its congeners. In Scotland, where pastures are 

 somewhat limited, it is dreaded and detested almost as much as the Carrion-Crow. 

 It is certain that when pressed by hunger it will sacrifice weak birds to satisfy 

 its craving for food ; for, as noted in my " Handbook " I have on several 

 occasions witnessed this predatory habit in severe wintry weather. 



The Rook is essentially a gregarious bird and haunts well-cultivated districts, 

 preferabl}^ where tall trees are numerous and pastures are large ; here he may be 

 seen day after day busily feeding on snails or digging for worms, leather-jackets 

 and other noxious grubs ; in the fallows, whilst he doubtless swallows a little 

 grain, he does incalculable good by destroying wire-worms and larvae of cock- 

 chafers, whilst in the turnip-fields he not onl}' devours such examples of the 

 latter grubs as he can find, but does considerable execution upon the dreaded 

 and destructive caterpillar of a common moth (Agrotis segetuin) . 



The nests are generally placed in the upper branches of tall trees ; either in 

 copses, plantations, pleasure-grounds, parks, or when planted in rows bounding 

 the margin of a pasture, or forming an avenue over a country road ; but 

 Stevenson rightly says: — "Though for the most part selecting the tallest trees, 

 and placing their nest near the upper branches, they will build also on low 

 Scotch firs, in the most exposed situations," and he adds : — " A still more novel 

 site has also been chosen by a few pairs at Spixworth Park, where, for the last 

 two or three seasons, they have built in the tops of some fine laurustinus bushes, 

 about twelve or foiirteen feet from the ground, and others in a dwarf ilex, close 

 to a flight of stone steps, connecting one part of the garden with the other, yet 

 so low down that the feeding of the young was plainly visible fi^om the windows 

 of the hall." When a rookery is well established, the birds are not easily 

 persuaded to abandon it, excepting for private reasons of their own ; moreover the 



